it goes in the PCI slot.. and i would use it purely for Physx processing.. nothing else..

i was also wondering why in EVGA precision why my clock settings randomly drop.. i would think that when im running F@H for GPU it would stay at the OC clock settings but it doesn't.. after a little bit it just drops.. to low settings that make folding suck.. same with 3D games.. IDK why.. can someone explain this to me?

You said in your first post that you are trying to run the card at overclocked settings. If you aren't overclocked and it still happens, there's a possibility that you're having a power issue, given the fact that you're using a garbage power supply. The card may be throttling because it isn't getting enough juice.